Unplanned cancer presentation in patients with psychiatric disorders: A nationwide register-based cohort study in Denmark.

Unplanned presentation in the cancer pathway is more common in patients with psychiatric disorders than in patients without. More knowledge about the risk factors for unplanned presentation could help target interventions to ensure earlier diagnosis of cancer in patients with psychiatric disorders. This study aims to estimate the association between patient characteristics (social characteristics and coexisting physical morbidity) and cancer diagnosis following unplanned presentation among cancer patients with psychiatric disorders. We conducted a population-based register study including patients diagnosed with cancer in 2014-2018 and also registered with at least one psychiatric disorder in the included Danish registers (n = 26,005). We used logistic regression to assess patient characteristics associated with an unplanned presentation. Almost one in four symptomatic patients (23.6 %) with pre-existing psychiatric disorders presented unplanned in the cancer trajectory. Unplanned presentation was most common for severe psychiatric disorders, e.g. organic disorders and schizophrenia. Old age, male sex, living alone, low education, physical comorbidity, and non-attendance in primary care were associated with increased odds of unplanned presentation. In conclusion, several characteristics of patients with pre-existing psychiatric disorders were associated with unplanned presentation in the cancer trajectory; for some groups more than 40 % had an unplanned presentation. This information could be used to design targeted interventions for patients with pre-existing psychiatric disorders to ensure earlier diagnosis of cancer in this population.